Becker Patrick, Döhmann Annemieke, Wöhlbrand Lars, Thies Daniela, Hinrichs Christina, Buschen Ramona, Wünsch Daniel, Neumann-Schaal Meina, Schomburg Dietmar, Winklhofer Michael, Reinhardt Richard, Rabus Ralf
General and Molecular Microbiology, Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg, Germany.
Department of Microbiology, Max Planck Institute for Marine Microbiology, Bremen, Germany.
Environ Microbiol. 2022 Jul;24(7):3195-3211. doi: 10.1111/1462-2920.16074. Epub 2022 Jun 7.
Large quantities of organic matter are continuously deposited, and (a)biotic gradients intersect in the soil-rhizosphere, where biodegradation contributes to the global cycles of elements. The betaproteobacterial genus Aromatoleum comprises cosmopolitan, facultative denitrifying degradation specialists. Aromatoleum aromaticum. pCyN1 stands out for anaerobically decomposing plant-derived monoterpenes in addition to monoaromatic hydrocarbons, polar aromatics and aliphatics. The catabolic network's structure and flexibility in A. aromaticum pCyN1 were studied across 34 growth conditions by superimposing proteome profiles onto the manually annotated 4.37 Mbp genome. Strain pCyN1 employs three fundamentally different enzymes for C-H-bond cleavage at the methyl groups of p-cymene/4-ethyltoluene, toluene and p-cresol respectively. Regulation of degradation modules displayed substrate specificities ranging from narrow (toluene and cyclohexane carboxylate) via medium-wide (one module shared by p-cymene, 4-ethyltoluene, α-phellandrene, α-terpinene, γ-terpinene and limonene) to broad (central benzoyl-CoA pathway serving 16 aromatic substrates). Remarkably, three variants of ATP-dependent (class I) benzoyl-CoA reductase and four different β-oxidation routes establish a degradation hub that accommodates the substrate diversity. The respiratory system displayed several conspicuous profiles, e.g. the presence of nitrous oxide reductase under oxic and of low-affinity oxidase under anoxic conditions. Overall, nutritional versatility in conjunction with network regulation endow A. aromaticum pCyN1 with broad adaptability.
大量的有机物质不断沉积，（非）生物梯度在土壤-根际相交，生物降解在其中促进了元素的全球循环。β-变形菌属的芳香油杆菌属包含世界性的兼性反硝化降解专家。芳香油杆菌。pCyN1除了能厌氧分解单芳烃、极性芳烃和脂肪族化合物外，还能厌氧分解植物衍生的单萜。通过将蛋白质组图谱叠加到人工注释的4.37Mbp基因组上，在34种生长条件下研究了芳香油杆菌pCyN1分解代谢网络的结构和灵活性。菌株pCyN1分别使用三种根本不同的酶在对异丙基苯/4-乙基甲苯、甲苯和对甲酚的甲基处进行C-H键裂解。降解模块的调控显示出底物特异性，范围从狭窄（甲苯和环己烷羧酸盐）到中等宽泛（对异丙基苯、4-乙基甲苯、α-水芹烯、α-松油烯、γ-松油烯和柠檬烯共享一个模块）再到宽泛（中央苯甲酰辅酶A途径服务于16种芳香底物）。值得注意的是，三种ATP依赖性（I类）苯甲酰辅酶A还原酶变体和四种不同的β-氧化途径建立了一个适应底物多样性的降解中心。呼吸系统显示出几种显著的特征，例如在有氧条件下存在一氧化二氮还原酶，在无氧条件下存在低亲和力氧化酶。总体而言，营养多样性与网络调控赋予了芳香油杆菌pCyN1广泛的适应性。
